lhecking at users.sourceforge.net wrote: >>I guess you need to look at the bonding src code - looks like it is in >>drivers/net/bonding/bond_main.c - for CentOS 5 it is: > > > C xor is bitwise. > > I did a bit of scripting and found that the algorithm seems much more > sensitive to port numbers than IP addresses. Not that iperf gives much > control over those, it looks like the client port numbers are picked at > random. As a result, I would expect to repeat this test on the same set > of clients, say, hundreds of times, and maybe find a small number of > cases where all interfaces are utilised. You could use xmit_hash_policy=layer2+3 - which just uses MAC and IP addresses (which you do have more control over) - and see if you can pick a mix of IP/MAC addresses that would result in all four interfaces being used (theoretically) - and see if it matches reality? James Pearson